/***************************************************************************/
/*                                                                         */
/*  ttsbit0.c                                                              */
/*                                                                         */
/*    TrueType and OpenType embedded bitmap support (body).                */
/*    This is a heap-optimized version.                                    */
/*                                                                         */
/*  Copyright 2005, 2006, 2007, 2008, 2009 by                              */
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/


/* This file is included by ttsbit.c */


#include <ft2build.h>
#include FT_INTERNAL_DEBUG_H
#include FT_INTERNAL_STREAM_H
#include FT_TRUETYPE_TAGS_H
#include "ttsbit.h"

#include "sferrors.h"


/*************************************************************************/
/*                                                                       */
/* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
/* messages during execution.                                            */
/*                                                                       */
#undef  FT_COMPONENT
#define FT_COMPONENT trace_ttsbit


FT_LOCAL_DEF(FT_Error)
tt_face_load_eblc(TT_Face face,
                  FT_Stream stream)
{
    FT_Error error = SFNT_Err_Ok;
    FT_Fixed version;
    FT_ULong num_strikes, table_size;
    FT_Byte* p;
    FT_Byte* p_limit;
    FT_UInt count;


    face->sbit_num_strikes = 0;

    /* this table is optional */
    error = face->goto_table(face, TTAG_EBLC, stream, &table_size);
    if (error)
        error = face->goto_table(face, TTAG_bloc, stream, &table_size);
    if (error)
        goto Exit;

    if (table_size < 8)
    {
        FT_ERROR(("tt_face_load_sbit_strikes: table too short\n"));
        error = SFNT_Err_Invalid_File_Format;
        goto Exit;
    }

    if (FT_FRAME_EXTRACT(table_size, face->sbit_table))
        goto Exit;

    face->sbit_table_size = table_size;

    p = face->sbit_table;
    p_limit = p + table_size;

    version = FT_NEXT_ULONG(p);
    num_strikes = FT_NEXT_ULONG(p);

    if (version != 0x00020000UL || num_strikes >= 0x10000UL)
    {
        FT_ERROR(("tt_face_load_sbit_strikes: invalid table version\n"));
        error = SFNT_Err_Invalid_File_Format;
        goto Fail;
    }

    /*
     *  Count the number of strikes available in the table.  We are a bit
     *  paranoid there and don't trust the data.
     */
    count = (FT_UInt)num_strikes;
    if (8 + 48UL * count > table_size)
        count = (FT_UInt)((p_limit - p) / 48);

    face->sbit_num_strikes = count;

    FT_TRACE3(("sbit_num_strikes: %u\n", count));
Exit:
    return error;

Fail:
    FT_FRAME_RELEASE(face->sbit_table);
    face->sbit_table_size = 0;
    goto Exit;
}


FT_LOCAL_DEF(void)
tt_face_free_eblc(TT_Face face)
{
    FT_Stream stream = face->root.stream;


    FT_FRAME_RELEASE(face->sbit_table);
    face->sbit_table_size = 0;
    face->sbit_num_strikes = 0;
}


FT_LOCAL_DEF(FT_Error)
tt_face_set_sbit_strike(TT_Face face,
                        FT_Size_Request req,
                        FT_ULong * astrike_index)
{
    return FT_Match_Size((FT_Face)face, req, 0, astrike_index);
}


FT_LOCAL_DEF(FT_Error)
tt_face_load_strike_metrics(TT_Face face,
                            FT_ULong strike_index,
                            FT_Size_Metrics * metrics)
{
    FT_Byte* strike;


    if (strike_index >= (FT_ULong)face->sbit_num_strikes)
        return SFNT_Err_Invalid_Argument;

    strike = face->sbit_table + 8 + strike_index * 48;

    metrics->x_ppem = (FT_UShort)strike[44];
    metrics->y_ppem = (FT_UShort)strike[45];

    metrics->ascender = (FT_Char)strike[16] << 6;   /* hori.ascender  */
    metrics->descender = (FT_Char)strike[17] << 6;  /* hori.descender */
    metrics->height = metrics->ascender - metrics->descender;

    /* XXX: Is this correct? */
    metrics->max_advance = ((FT_Char)strike[22] +  /* min_origin_SB  */
                            strike[18] +           /* max_width      */
                            (FT_Char)strike[23]    /* min_advance_SB */
                            ) << 6;

    return SFNT_Err_Ok;
}


typedef struct  TT_SBitDecoderRec_
{
    TT_Face face;
    FT_Stream stream;
    FT_Bitmap* bitmap;
    TT_SBit_Metrics metrics;
    FT_Bool metrics_loaded;
    FT_Bool bitmap_allocated;
    FT_Byte bit_depth;

    FT_ULong ebdt_start;
    FT_ULong ebdt_size;

    FT_ULong strike_index_array;
    FT_ULong strike_index_count;
    FT_Byte* eblc_base;
    FT_Byte* eblc_limit;

} TT_SBitDecoderRec, * TT_SBitDecoder;


static FT_Error
tt_sbit_decoder_init(TT_SBitDecoder decoder,
                     TT_Face face,
                     FT_ULong strike_index,
                     TT_SBit_MetricsRec* metrics)
{
    FT_Error error;
    FT_Stream stream = face->root.stream;
    FT_ULong ebdt_size;


    error = face->goto_table(face, TTAG_EBDT, stream, &ebdt_size);
    if (error)
        error = face->goto_table(face, TTAG_bdat, stream, &ebdt_size);
    if (error)
        goto Exit;

    decoder->face = face;
    decoder->stream = stream;
    decoder->bitmap = &face->root.glyph->bitmap;
    decoder->metrics = metrics;

    decoder->metrics_loaded = 0;
    decoder->bitmap_allocated = 0;

    decoder->ebdt_start = FT_STREAM_POS();
    decoder->ebdt_size = ebdt_size;

    decoder->eblc_base = face->sbit_table;
    decoder->eblc_limit = face->sbit_table + face->sbit_table_size;

    /* now find the strike corresponding to the index */
    {
        FT_Byte* p;


        if (8 + 48 * strike_index + 3 * 4 + 34 + 1 > face->sbit_table_size)
        {
            error = SFNT_Err_Invalid_File_Format;
            goto Exit;
        }

        p = decoder->eblc_base + 8 + 48 * strike_index;

        decoder->strike_index_array = FT_NEXT_ULONG(p);
        p += 4;
        decoder->strike_index_count = FT_NEXT_ULONG(p);
        p += 34;
        decoder->bit_depth = *p;

        if (decoder->strike_index_array > face->sbit_table_size ||
            decoder->strike_index_array + 8 * decoder->strike_index_count >
            face->sbit_table_size)
            error = SFNT_Err_Invalid_File_Format;
    }

Exit:
    return error;
}


static void
tt_sbit_decoder_done(TT_SBitDecoder decoder)
{
    FT_UNUSED(decoder);
}


static FT_Error
tt_sbit_decoder_alloc_bitmap(TT_SBitDecoder decoder)
{
    FT_Error error = SFNT_Err_Ok;
    FT_UInt width, height;
    FT_Bitmap* map = decoder->bitmap;
    FT_Long size;


    if (!decoder->metrics_loaded)
    {
        error = SFNT_Err_Invalid_Argument;
        goto Exit;
    }

    width = decoder->metrics->width;
    height = decoder->metrics->height;

    map->width = (int)width;
    map->rows = (int)height;

    switch (decoder->bit_depth)
    {
        case 1:
            map->pixel_mode = FT_PIXEL_MODE_MONO;
            map->pitch = (map->width + 7) >> 3;
            break;

        case 2:
            map->pixel_mode = FT_PIXEL_MODE_GRAY2;
            map->pitch = (map->width + 3) >> 2;
            break;

        case 4:
            map->pixel_mode = FT_PIXEL_MODE_GRAY4;
            map->pitch = (map->width + 1) >> 1;
            break;

        case 8:
            map->pixel_mode = FT_PIXEL_MODE_GRAY;
            map->pitch = map->width;
            break;

        default:
            error = SFNT_Err_Invalid_File_Format;
            goto Exit;
    }

    size = map->rows * map->pitch;

    /* check that there is no empty image */
    if (size == 0)
        goto Exit;   /* exit successfully! */

    error = ft_glyphslot_alloc_bitmap(decoder->face->root.glyph, size);
    if (error)
        goto Exit;

    decoder->bitmap_allocated = 1;

Exit:
    return error;
}


static FT_Error
tt_sbit_decoder_load_metrics(TT_SBitDecoder decoder,
                             FT_Byte** pp,
                             FT_Byte* limit,
                             FT_Bool big)
{
    FT_Byte* p = *pp;
    TT_SBit_Metrics metrics = decoder->metrics;


    if (p + 5 > limit)
        goto Fail;

    metrics->height = p[0];
    metrics->width = p[1];
    metrics->horiBearingX = (FT_Char)p[2];
    metrics->horiBearingY = (FT_Char)p[3];
    metrics->horiAdvance = p[4];

    p += 5;
    if (big)
    {
        if (p + 3 > limit)
            goto Fail;

        metrics->vertBearingX = (FT_Char)p[0];
        metrics->vertBearingY = (FT_Char)p[1];
        metrics->vertAdvance = p[2];

        p += 3;
    }

    decoder->metrics_loaded = 1;
    *pp = p;
    return SFNT_Err_Ok;

Fail:
    return SFNT_Err_Invalid_Argument;
}


/* forward declaration */
static FT_Error
tt_sbit_decoder_load_image(TT_SBitDecoder decoder,
                           FT_UInt glyph_index,
                           FT_Int x_pos,
                           FT_Int y_pos);

typedef FT_Error (*TT_SBitDecoder_LoadFunc)(TT_SBitDecoder decoder,
                                            FT_Byte* p,
                                            FT_Byte* plimit,
                                            FT_Int x_pos,
                                            FT_Int y_pos);


static FT_Error
tt_sbit_decoder_load_byte_aligned(TT_SBitDecoder decoder,
                                  FT_Byte* p,
                                  FT_Byte* limit,
                                  FT_Int x_pos,
                                  FT_Int y_pos)
{
    FT_Error error = SFNT_Err_Ok;
    FT_Byte* line;
    FT_Int bit_height, bit_width, pitch, width, height, h;
    FT_Bitmap* bitmap;


    if (!decoder->bitmap_allocated)
    {
        error = tt_sbit_decoder_alloc_bitmap(decoder);
        if (error)
            goto Exit;
    }

    /* check that we can write the glyph into the bitmap */
    bitmap = decoder->bitmap;
    bit_width = bitmap->width;
    bit_height = bitmap->rows;
    pitch = bitmap->pitch;
    line = bitmap->buffer;

    width = decoder->metrics->width;
    height = decoder->metrics->height;

    if (x_pos < 0 || x_pos + width > bit_width ||
        y_pos < 0 || y_pos + height > bit_height)
    {
        error = SFNT_Err_Invalid_File_Format;
        goto Exit;
    }

    if (p + ((width + 7) >> 3) * height > limit)
    {
        error = SFNT_Err_Invalid_File_Format;
        goto Exit;
    }

    /* now do the blit */
    line += y_pos * pitch + (x_pos >> 3);
    x_pos &= 7;

    if (x_pos == 0)    /* the easy one */
    {
        for (h = height; h > 0; h--, line += pitch)
        {
            FT_Byte* write = line;
            FT_Int w;


            for (w = width; w >= 8; w -= 8)
            {
                write[0] = (FT_Byte)(write[0] | *p++);
                write += 1;
            }

            if (w > 0)
                write[0] = (FT_Byte)(write[0] | (*p++ & (0xFF00U >> w)));
        }
    }
    else  /* x_pos > 0 */
    {
        for (h = height; h > 0; h--, line += pitch)
        {
            FT_Byte* write = line;
            FT_Int w;
            FT_UInt wval = 0;


            for (w = width; w >= 8; w -= 8)
            {
                wval = (FT_UInt)(wval | *p++);
                write[0] = (FT_Byte)(write[0] | (wval >> x_pos));
                write += 1;
                wval <<= 8;
            }

            if (w > 0)
                wval = (FT_UInt)(wval | (*p++ & (0xFF00U >> w)));

            /* all bits read and there are `x_pos + w' bits to be written */

            write[0] = (FT_Byte)(write[0] | (wval >> x_pos));

            if (x_pos + w > 8)
            {
                write++;
                wval <<= 8;
                write[0] = (FT_Byte)(write[0] | (wval >> x_pos));
            }
        }
    }

Exit:
    return error;
}


/*
 * Load a bit-aligned bitmap (with pointer `p') into a line-aligned bitmap
 * (with pointer `write').  In the example below, the width is 3 pixel,
 * and `x_pos' is 1 pixel.
 *
 *       p                               p+1
 *     |                               |                               |
 *     | 7   6   5   4   3   2   1   0 | 7   6   5   4   3   2   1   0 |...
 *     |                               |                               |
 *       +-------+   +-------+   +-------+ ...
 *           .           .           .
 *           .           .           .
 *           v           .           .
 *       +-------+       .           .
 * |                               | .
 * | 7   6   5   4   3   2   1   0 | .
 * |                               | .
 *   write               .           .
 *                       .           .
 *                       v           .
 *                   +-------+       .
 *             |                               |
 *             | 7   6   5   4   3   2   1   0 |
 *             |                               |
 *               write+1             .
 *                                   .
 *                                   v
 *                               +-------+
 *                         |                               |
 *                         | 7   6   5   4   3   2   1   0 |
 *                         |                               |
 *                           write+2
 *
 */

static FT_Error
tt_sbit_decoder_load_bit_aligned(TT_SBitDecoder decoder,
                                 FT_Byte* p,
                                 FT_Byte* limit,
                                 FT_Int x_pos,
                                 FT_Int y_pos)
{
    FT_Error error = SFNT_Err_Ok;
    FT_Byte* line;
    FT_Int bit_height, bit_width, pitch, width, height, h, nbits;
    FT_Bitmap* bitmap;
    FT_UShort rval;


    if (!decoder->bitmap_allocated)
    {
        error = tt_sbit_decoder_alloc_bitmap(decoder);
        if (error)
            goto Exit;
    }

    /* check that we can write the glyph into the bitmap */
    bitmap = decoder->bitmap;
    bit_width = bitmap->width;
    bit_height = bitmap->rows;
    pitch = bitmap->pitch;
    line = bitmap->buffer;

    width = decoder->metrics->width;
    height = decoder->metrics->height;

    if (x_pos < 0 || x_pos + width > bit_width ||
        y_pos < 0 || y_pos + height > bit_height)
    {
        error = SFNT_Err_Invalid_File_Format;
        goto Exit;
    }

    if (p + ((width * height + 7) >> 3) > limit)
    {
        error = SFNT_Err_Invalid_File_Format;
        goto Exit;
    }

    /* now do the blit */

    /* adjust `line' to point to the first byte of the bitmap */
    line += y_pos * pitch + (x_pos >> 3);
    x_pos &= 7;

    /* the higher byte of `rval' is used as a buffer */
    rval = 0;
    nbits = 0;

    for (h = height; h > 0; h--, line += pitch)
    {
        FT_Byte* write = line;
        FT_Int w = width;


        /* handle initial byte (in target bitmap) specially if necessary */
        if (x_pos)
        {
            w = (width < 8 - x_pos) ? width : 8 - x_pos;

            if (h == height)
            {
                rval = *p++;
                nbits = x_pos;
            }
            else if (nbits < w)
            {
                if (p < limit)
                    rval |= *p++;
                nbits += 8 - w;
            }
            else
            {
                rval >>= 8;
                nbits -= w;
            }

            *write++ |= ((rval >> nbits) & 0xFF) &
                        (~(0xFF << w) << (8 - w - x_pos));
            rval <<= 8;

            w = width - w;
        }

        /* handle medial bytes */
        for (; w >= 8; w -= 8)
        {
            rval |= *p++;
            *write++ |= (rval >> nbits) & 0xFF;

            rval <<= 8;
        }

        /* handle final byte if necessary */
        if (w > 0)
        {
            if (nbits < w)
            {
                if (p < limit)
                    rval |= *p++;
                *write |= ((rval >> nbits) & 0xFF) & (0xFF00U >> w);
                nbits += 8 - w;

                rval <<= 8;
            }
            else
            {
                *write |= ((rval >> nbits) & 0xFF) & (0xFF00U >> w);
                nbits -= w;
            }
        }
    }

Exit:
    return error;
}


static FT_Error
tt_sbit_decoder_load_compound(TT_SBitDecoder decoder,
                              FT_Byte* p,
                              FT_Byte* limit,
                              FT_Int x_pos,
                              FT_Int y_pos)
{
    FT_Error error = SFNT_Err_Ok;
    FT_UInt num_components, nn;

    FT_Char horiBearingX = decoder->metrics->horiBearingX;
    FT_Char horiBearingY = decoder->metrics->horiBearingY;
    FT_Byte horiAdvance = decoder->metrics->horiAdvance;
    FT_Char vertBearingX = decoder->metrics->vertBearingX;
    FT_Char vertBearingY = decoder->metrics->vertBearingY;
    FT_Byte vertAdvance = decoder->metrics->vertAdvance;


    if (p + 2 > limit)
        goto Fail;

    num_components = FT_NEXT_USHORT(p);
    if (p + 4 * num_components > limit)
        goto Fail;

    if (!decoder->bitmap_allocated)
    {
        error = tt_sbit_decoder_alloc_bitmap(decoder);
        if (error)
            goto Exit;
    }

    for (nn = 0; nn < num_components; nn++)
    {
        FT_UInt gindex = FT_NEXT_USHORT(p);
        FT_Byte dx = FT_NEXT_BYTE(p);
        FT_Byte dy = FT_NEXT_BYTE(p);


        /* NB: a recursive call */
        error = tt_sbit_decoder_load_image(decoder, gindex,
                                           x_pos + dx, y_pos + dy);
        if (error)
            break;
    }

    decoder->metrics->horiBearingX = horiBearingX;
    decoder->metrics->horiBearingY = horiBearingY;
    decoder->metrics->horiAdvance = horiAdvance;
    decoder->metrics->vertBearingX = vertBearingX;
    decoder->metrics->vertBearingY = vertBearingY;
    decoder->metrics->vertAdvance = vertAdvance;
    decoder->metrics->width = (FT_UInt)decoder->bitmap->width;
    decoder->metrics->height = (FT_UInt)decoder->bitmap->rows;

Exit:
    return error;

Fail:
    error = SFNT_Err_Invalid_File_Format;
    goto Exit;
}


static FT_Error
tt_sbit_decoder_load_bitmap(TT_SBitDecoder decoder,
                            FT_UInt glyph_format,
                            FT_ULong glyph_start,
                            FT_ULong glyph_size,
                            FT_Int x_pos,
                            FT_Int y_pos)
{
    FT_Error error;
    FT_Stream stream = decoder->stream;
    FT_Byte* p;
    FT_Byte* p_limit;
    FT_Byte* data;


    /* seek into the EBDT table now */
    if (glyph_start + glyph_size > decoder->ebdt_size)
    {
        error = SFNT_Err_Invalid_Argument;
        goto Exit;
    }

    if (FT_STREAM_SEEK(decoder->ebdt_start + glyph_start) ||
        FT_FRAME_EXTRACT(glyph_size, data))
        goto Exit;

    p = data;
    p_limit = p + glyph_size;

    /* read the data, depending on the glyph format */
    switch (glyph_format)
    {
        case 1:
        case 2:
        case 8:
            error = tt_sbit_decoder_load_metrics(decoder, &p, p_limit, 0);
            break;

        case 6:
        case 7:
        case 9:
            error = tt_sbit_decoder_load_metrics(decoder, &p, p_limit, 1);
            break;

        default:
            error = SFNT_Err_Ok;
    }

    if (error)
        goto Fail;

    {
        TT_SBitDecoder_LoadFunc loader;


        switch (glyph_format)
        {
            case 1:
            case 6:
                loader = tt_sbit_decoder_load_byte_aligned;
                break;

            case 2:
            case 5:
            case 7:
                loader = tt_sbit_decoder_load_bit_aligned;
                break;

            case 8:
                if (p + 1 > p_limit)
                    goto Fail;

                p += 1; /* skip padding */
            /* fall-through */

            case 9:
                loader = tt_sbit_decoder_load_compound;
                break;

            default:
                goto Fail;
        }

        error = loader(decoder, p, p_limit, x_pos, y_pos);
    }

Fail:
    FT_FRAME_RELEASE(data);

Exit:
    return error;
}


static FT_Error
tt_sbit_decoder_load_image(TT_SBitDecoder decoder,
                           FT_UInt glyph_index,
                           FT_Int x_pos,
                           FT_Int y_pos)
{
    /*
     *  First, we find the correct strike range that applies to this
     *  glyph index.
     */

    FT_Byte* p = decoder->eblc_base + decoder->strike_index_array;
    FT_Byte* p_limit = decoder->eblc_limit;
    FT_ULong num_ranges = decoder->strike_index_count;
    FT_UInt start, end, index_format, image_format;
    FT_ULong image_start = 0, image_end = 0, image_offset;


    for (; num_ranges > 0; num_ranges--)
    {
        start = FT_NEXT_USHORT(p);
        end = FT_NEXT_USHORT(p);

        if (glyph_index >= start && glyph_index <= end)
            goto FoundRange;

        p += 4; /* ignore index offset */
    }
    goto NoBitmap;

FoundRange:
    image_offset = FT_NEXT_ULONG(p);

    /* overflow check */
    if (decoder->eblc_base + decoder->strike_index_array + image_offset <
        decoder->eblc_base)
        goto Failure;

    p = decoder->eblc_base + decoder->strike_index_array + image_offset;
    if (p + 8 > p_limit)
        goto NoBitmap;

    /* now find the glyph's location and extend within the ebdt table */
    index_format = FT_NEXT_USHORT(p);
    image_format = FT_NEXT_USHORT(p);
    image_offset = FT_NEXT_ULONG(p);

    switch (index_format)
    {
        case 1: /* 4-byte offsets relative to `image_offset' */
        {
            p += 4 * (glyph_index - start);
            if (p + 8 > p_limit)
                goto NoBitmap;

            image_start = FT_NEXT_ULONG(p);
            image_end = FT_NEXT_ULONG(p);

            if (image_start == image_end) /* missing glyph */
                goto NoBitmap;
        }
        break;

        case 2: /* big metrics, constant image size */
        {
            FT_ULong image_size;


            if (p + 12 > p_limit)
                goto NoBitmap;

            image_size = FT_NEXT_ULONG(p);

            if (tt_sbit_decoder_load_metrics(decoder, &p, p_limit, 1))
                goto NoBitmap;

            image_start = image_size * (glyph_index - start);
            image_end = image_start + image_size;
        }
        break;

        case 3: /* 2-byte offsets relative to 'image_offset' */
        {
            p += 2 * (glyph_index - start);
            if (p + 4 > p_limit)
                goto NoBitmap;

            image_start = FT_NEXT_USHORT(p);
            image_end = FT_NEXT_USHORT(p);

            if (image_start == image_end) /* missing glyph */
                goto NoBitmap;
        }
        break;

        case 4: /* sparse glyph array with (glyph,offset) pairs */
        {
            FT_ULong mm, num_glyphs;


            if (p + 4 > p_limit)
                goto NoBitmap;

            num_glyphs = FT_NEXT_ULONG(p);

            /* overflow check */
            if (p + (num_glyphs + 1) * 4 < p)
                goto Failure;

            if (p + (num_glyphs + 1) * 4 > p_limit)
                goto NoBitmap;

            for (mm = 0; mm < num_glyphs; mm++)
            {
                FT_UInt gindex = FT_NEXT_USHORT(p);


                if (gindex == glyph_index)
                {
                    image_start = FT_NEXT_USHORT(p);
                    p += 2;
                    image_end = FT_PEEK_USHORT(p);
                    break;
                }
                p += 2;
            }

            if (mm >= num_glyphs)
                goto NoBitmap;
        }
        break;

        case 5: /* constant metrics with sparse glyph codes */
        {
            FT_ULong image_size, mm, num_glyphs;


            if (p + 16 > p_limit)
                goto NoBitmap;

            image_size = FT_NEXT_ULONG(p);

            if (tt_sbit_decoder_load_metrics(decoder, &p, p_limit, 1))
                goto NoBitmap;

            num_glyphs = FT_NEXT_ULONG(p);

            /* overflow check */
            if (p + 2 * num_glyphs < p)
                goto Failure;

            if (p + 2 * num_glyphs > p_limit)
                goto NoBitmap;

            for (mm = 0; mm < num_glyphs; mm++)
            {
                FT_UInt gindex = FT_NEXT_USHORT(p);


                if (gindex == glyph_index)
                    break;
            }

            if (mm >= num_glyphs)
                goto NoBitmap;

            image_start = image_size * mm;
            image_end = image_start + image_size;
        }
        break;

        default:
            goto NoBitmap;
    }

    if (image_start > image_end)
        goto NoBitmap;

    image_end -= image_start;
    image_start = image_offset + image_start;

    return tt_sbit_decoder_load_bitmap(decoder,
                                       image_format,
                                       image_start,
                                       image_end,
                                       x_pos,
                                       y_pos);

Failure:
    return SFNT_Err_Invalid_Table;

NoBitmap:
    return SFNT_Err_Invalid_Argument;
}


FT_LOCAL(FT_Error)
tt_face_load_sbit_image(TT_Face face,
                        FT_ULong strike_index,
                        FT_UInt glyph_index,
                        FT_UInt load_flags,
                        FT_Stream stream,
                        FT_Bitmap * map,
                        TT_SBit_MetricsRec * metrics)
{
    TT_SBitDecoderRec decoder[1];
    FT_Error error;

    FT_UNUSED(load_flags);
    FT_UNUSED(stream);
    FT_UNUSED(map);


    error = tt_sbit_decoder_init(decoder, face, strike_index, metrics);
    if (!error)
    {
        error = tt_sbit_decoder_load_image(decoder, glyph_index, 0, 0);
        tt_sbit_decoder_done(decoder);
    }

    return error;
}

/* EOF */